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1.
A new dinuclear complex [Cu2(OAc)2(OH)(dpa)2] PF6 · H2O (1) is prepared and structurally and magneto-structurally characterized. The monocationic core contains one acetate in familiar bidentate η112-bridge and another in the rare monoatomic bridge along with one hydroxo intermediary. 1 packs through N–H…O and O–H…O hydrogen bonds and π…π interaction resulting a 3D supramolecular continuum and displays high-energy intraligand 1(π − π*) fluorescence and intraligand 3(π − π*) phosphorescence in glassy solution.  相似文献   
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Secondhand electronic cigarette (e-cigarette) aerosol (SHA) might impair indoor air quality and expose bystanders. This study aims to investigate exposure to SHA in controlled conditions of enclosed settings simulating real-world scenario. An experiment was performed in a car and in a room, in which SHA was generated during a 30-minute ad libitum use of an e-cigarette. The experiment was replicated on five consecutive days in each setting. We measured PM2.5, airborne nicotine concentrations, and biomarkers of exposure to SHA, such as nicotine metabolites, tobacco-specific nitrosamines, propylene glycol, and glycerol in bystanders’ saliva samples before, during, and after the exposure period. Self-reported health symptoms related to exposure to SHA were also recorded. The results showed that the highest median PM2.5 concentration was recorded during the exposure period, being 21 µg/m3 in the room setting and 16 µg/m3 in the car setting—about twofold increase compared to the baseline. Most concentrations of the airborne nicotine and all biomarkers were below the limit of quantification in both settings. Bystanders in both settings experienced some short-term irritation symptoms, expressed as dry throat, nose, eyes, and phlegm. In conclusion, short-term use of an e-cigarette in confined spaces increased indoor PM2.5 level and caused some irritation symptoms in bystanders.  相似文献   
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This paper deals with the relation between segmentation for coding and rate control. The efficiency of a segmentation-based coding scheme heavily relies on this step that defines how many and which regions have to be segmented. In this paper, we show that this problem can be formulated as a rate/distortion problem. The proposed solution not only controls the segmentation, but also defines the coding strategy to be used in each region. Together with the general approach, several simplified versions of the segmentation control are proposed and discussed.  相似文献   
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Osmotic treatment (OT) has been applied to infuse phenolic compounds into a model food. Two commercial grape extracts were used as a source of phenolics, a grape seed extract (GSE) and a white grape marc extract (WGME). Three different concentrations of total phenolics were applied with and without presence of osmo-active solute (50 g/100 g and 0 g/100 g of sucrose) in the osmotic solution (OS). With a 50 g/100 g sucrose and a total phenolic content in OS ranging from 3 g/L to 15 g/L and operating time up to 8 h, the final total phenolic content in the osmo-treated model food was between 815 mg GAE/kg and 7176 mg GAE/kg. That is between the 0.5 and 1.5 times higher than that of the richest fruits. A soaking process with the same phenolic content but with no sucrose in OS led to a total phenolic content in the model food that was between 80% and 100% higher.Mass transfer of the major phenolics infused into the model food during OT and soaking process was characterized considering the diffusional approach and Peleg's model. Progress of total and individual phenolic content fitted well both models with the exception of the flavan-3-ol dimer concentration.  相似文献   
5.
Procyanidin effects on adipocyte-related pathologies   总被引:1,自引:0,他引:1  
Procyanidins, a class of flavonoids, have clear and well-defined beneficial effects against several pathologies including cardiovascular heart disease. Now, studies in vivo are revealing the effects of procyanidins against obesity, where they prevent weight gain and adipose tissue mass increase, and against diabetes and insulin resistance, where they act as antihiperglycemic agents. Several mechanisms may be responsible for these effects. One of these, due to the key role of adipose tissue in the development of obesity and insulin resistance, is their effect on adipocytes. In this review we compile the studies that indicate a protective role for procyanidins in obesity and insulin resistance, focusing on their effects on the adipocyte, where procyanidins modify lipid synthesis, lipid degradation, glucose uptake, and adipose differentiation.  相似文献   
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This article reviews existing methods for the characterisation of mixing and flow in microchannels, micromixers and microreactors. In particular, it analyses the current experimental techniques and methods available for characterising mixing and the associated phenomena in single and multiphase flow. The review shows that the majority of the experimental techniques used for characterising mixing and two-phase flow in microchannels employ optical methods, which require optical access to the flow, or off-line measurements. Indeed visual measurements are very important for the fundamental understanding of the physics of these flows and the rapid advances in optical measurement techniques, like confocal scanning laser microscopy and high resolution stereo micro particle image velocimetry, are now making full field data retrieval possible. However, integration of microchannel devices in industrial processes will require on-line measurements for process control that do not necessarily rely on optical techniques. Developments are being made in the areas of non-intrusive sensors, magnetic resonance techniques, ultrasonic spectroscopy and on-line flow through measurement cells. The advances made in these areas will certainly be of increasing interest in the future as microchannels are more frequently employed in continuous flow equipment for industrial applications.  相似文献   
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Shape from incomplete silhouettes based on the reprojection error   总被引:1,自引:0,他引:1  
Traditional shape from silhouette methods compute the 3D shape as the intersection of the back-projected silhouettes in the 3D space, the so called visual hull. However, silhouettes that have been obtained with background subtraction techniques often present miss-detection errors (produced by false negatives or occlusions) which produce incomplete 3D shapes. Our approach deals with miss-detections, false alarms, and noise in the silhouettes. We recover the voxel occupancy which describes the 3D shape by minimizing an energy based on an approximation of the error between the shape 2D projections and the silhouettes. Two variants of the projection – and as a result the energy – as a function of the voxel occupancy are proposed. One of these variants outperforms the other. The energy also includes a sparsity measure, a regularization term, and takes into account the visibility of the voxels in each view in order to handle self-occlusions.  相似文献   
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